is 2 2510971 - 1
has 755878 decimal digits
takes 0.174 GHz-days to do one PRP test
Last-known PrimeNet details:
Exponent is not assigned to anyone
0 primality tests remaining
ResidueStatus
L-LF2E247C1262DB1D1double-checked
PRP-unknown--unknown-

 Trial FactoringP-1 FactoringCombined
LimitGHz-daysProbabilityB1B2GHz-daysProbabilityGHz-daysProbabilityProb over default TF
Actual26823.737867.6471%32000001120000000.91808.0607%24.655870.2549%2.6079%
PrimeNet2590.030662.7119%110001900000.00212.6412%0.032763.6967%0.9848%
GPU722630.635665.0794%110001700000.00201.4087%0.637665.5713%0.4919%
Difference+5+23.1022+2.5677%+3189000+111830000+0.9160+6.6519%+24.0182+4.6836%+4.6836%

Known prime factors (1 factor, 74.8 bits, 0.00297810% known):
Remaining cofactor is not a probable-prime

P-1GHz-days
exponentfactordigitsbits*kdate foundmin B1min B2min. TFmin. P-1normal P-1
2510971324198269378918059887912374.7796455635476851745
32 × 5 × 19 × 31 × 243562930649
2020-05-13312435629306491,914.51,334.62,492.7

P-1 results:
 GHz-DaysworthFactor
probability
dateuseridcompidb1b2estagefactordigitsbits*spentsaved
2003-10-23T00:00:00ANONYMOUSv4_computers2048204800---0.001--0.235%
2003-10-31T00:00:00Team Prime Ribv4_computers15000236250---0.003--0.795%
2010-12-16T22:40:00Jocelyn LaroucheManual testing2000020000---0.002--0.264%
2011-01-01T00:57:00Jocelyn LaroucheManual testing3000030000---0.003--0.365%
2011-01-04T22:09:00Jocelyn LaroucheManual testing5000050000---0.005--0.529%
2011-10-04T06:11:00markrtiny1650003918750---0.037--3.099%
2016-02-24T02:11:39mikrMSI320000011200000012---0.918--8.061%


Trial Factoring results:
 BitsFactorGHz-Daysworth
dateuseridcompidfromtofactorbits*digitsspentsaved
1999-03-15T00:00:00ANONYMOUSv4_computers21259--0.031--
2016-02-23T16:29:15Mark RoseManual testing259260--0.031--
2009-01-30T20:20:00Sturle Sundeginy.ifi260261--0.061--
2012-06-12T20:31:00Sebastian HornbostelManual testing261262--0.122--
2013-01-23T08:30:00dbaughManual testing262263--0.391--
2015-02-18T11:36:00VictordeHollanderManual testing263264--0.782--
2015-02-18T11:36:00VictordeHollanderManual testing264265--1.488--
2015-11-05T09:47:21ramgeisManual testing265266--2.976--
2017-07-31T07:56:49Gordon SpenceManual testing266267--5.952--
2019-05-13T13:38:13TJAOIManual testing267268--11.90--


ECM factoring results:

Old Calculation Method

Total ECM effort:3.128 GHz-days
Estimated T-Level:1.700
DigitsB1CurvesCompleteFacMiss
201100034 / 1000.34071.055%
255000034 / 2800.12188.546%

New Calculation Method

Total ECM effort:3.128 GHz-days
Estimated T-Level:1.700
DigitsB1CompleteFacMiss
20110001.09733.395%
25500000.09990.563%
302500000.00699.391%


ECM Summary

B1B2factorcurvesGHz-days
500005000000333.036
50000500000010.092


Lucas-Lehmer results:
dateuseridcompidres64spent (GHz-days)
1999-04-02T00:00:00ANONYMOUSv4_computersF2E247C1262DB1D10.174
2018-06-04T07:17:40kkmrkkblmbrbkoldF2E247C1262DB1D10.174


PRP results:
dateuseridcompidcofactorsres64PRP
2020-05-13T12:31:28CrypticCluecruncher
32419826937891805988791
CFB3548DED8CEF1Ano
2020-05-13T13:11:08ATHec2-PRPCFDC
32419826937891805988791
CFB3548DED8CEF1Ano


P-1 factor-bounds graph:
B1 = 3200000, B2 = 112000000 (P-1 stage 2)
B1 = 3200000 (P-1 stage 1)
B1 = 165000, B2 = 3918750 (P-1 stage 2)
B1 = 165000 (P-1 stage 1)
B1 = 50000 (P-1 stage 1)
B1 = 30000 (P-1 stage 1)
B1 = 15000, B2 = 236250 (P-1 stage 2)
B1 = 20000 (P-1 stage 1)
B1 = 15000 (P-1 stage 1)
B1 = 2048, B2 = 204800 (P-1 stage 2)
B1 = 2048 (P-1 stage 1)
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TF factor-bounds graph:
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Last modified: 2020-05-13T13:11:08+00:00